PHENIX STATUS W.A. Zajc Columbia University for the PHENIX Collaboration

2 Outline l Collaboration l Schedule l Status l Physics Impact to date l Role of Spin in PHENIX

3 What is PHENIX? l Pioneering High Energy Nuclear Interaction eXperiment l Goals: o Broadest possible study of A-A, p-A, p-p collisions to uStudy nuclear matter under extreme conditions uUsing a wide variety of probes sensitive to all timescales uStudy systematic variations with species and energy o Measure spin structure of the nucleon èThese two programs have produced a detector with unparalleled capabilities

4 The PHENIX Collaboration A strongly international venture: è 11 nations Brazil, China, France, Germany, India, Israel, Japan, South Korea, Russia, Sweden, United States è 51 institutions

5 Schedule o 2 central spectrometers o 2 forward spectrometers o 3 global detectors

6 24-Jul-97

7 10-Jan-98

8 12-Jan-99

9 23-Dec-99

10 One Year Ago For years we’d been showing pictures of one “central” arm: 21-Jan-00: The real thing moves into place

11 Run-1 Configuration l Two central arms o Mechanically ~complete o Roughly half of aperture instrumented l Global detectors o Zero-degree Calorimeters (ZDCs) o Beam-Beam Counters (BBCs) o Multiplicity and Vertex Detector (MVD, engineering run)

12 Run-1 Accomplishments l First collisions:15-Jun-00 l Last collisions: 04-Sep-00 l During this period : o Commissioned uZero-Degree Calorimeters uBeam-Beam Counters uMultiplicity and Vertex Counter uDrift Chambers uPad Chambers uRing Imaging Cerenkov Counter uTime Expansion Chamber uTime-of-Flight Counters uElectromagnetic Calorimeter uMuon Identifier uMinimum Bias Triggers uData Acquisition System o Recorded ~5M minimum bias events

13 Run-1 Results l Global Event Features o Transverse Energy o Charged Multiplicity o Elliptic Flow l Identified Particles o Hadrons   , K , p    o ’s       HBT o Electrons l Studied versus o Centrality o Number of participants All results are for Au-Au collisions at

14 Run-1 Results This is a partial compilation

15 Physics Implications (??) Slide from seminar given last week by M. Gyulassy

16 Physics Impact

17 Run-1 Summary l PHENIX achieved its goals: o Completion of Year-1 u Mechanics u Electronics o Commissioning of all Year-1 sub-systems o Unbiased sample of RHIC events o Major physics impact while maintaining progress towards a Run-2 spin measurement: o Spin commissioning of one ring o Construction of South Muon Spectrometer l These successes would have been impossible without the RIKEN contributions

18 RBRC and RIKEN Roles in PHENIX (1) l PHENIX Muon Arm: En’yo, Ichihara, Imai, Kobayashi, Kurita, Mao. Murata, Saito, Sato, Shibata, Taketani, Tojo, Tori, Watanabe  PHENIX EMCal o Analysis of Au-Au Collision Data: Basilevsky, Goto, Tori o High Energy Beam Test: Goto, Imai, Saito, Tori l PHENIX Trigger o EMCal+RICH: Grosse-Perdekamp o LVL-2: Deshpande  PHENIX-CC-J: En’yo, Goto, Hayashi, Ichihara, Watanabe, Yokkaichi l PHENIX Luminosity Monitor: Bunce l PHENIX Drift Chamber: Grosse-Perdekamp

19 RBRC and RIKEN Roles in PHENIX (2)  PHENIX Calibration Task Force: Matthias l Polarimeter o RHIC Polarimeter: Bunce, Deshpande, Imai, Kurita, Saito, Tojo o AGS Polarimeter (E950/E925): Bunce, En’yo, Goto, Hayashi, Kurita, Saito, Sato o PHENIX Local Polarimeter: Goto, Saito l Future Planning o PHENIX Upgrades: Goto, Taketani o eRHIC: Deshpande  PHENIX “service” o Executive Council: En’yo o Local PHENIX-J Contact: Saito o Internal Review Committee: Grosse-Perdekamp o Speakers’ Bureau: Saito

20 This year l South Muon Spectrometer now in place l On-schedule for major contributions to o Upcoming spin run AND o Upcoming heavy ion run

21 Spin in PHENIX l Spin has been an integral part of PHENIX strategy and policy o In statements to BNL management o In all Beam Use Proposals o In the PHENIX Executive Council l The heavy ion program has benefited from this synergy: o In analysis of calorimeter data o In performing our data analysis (CC-J!) o In internal review of our first publications l We look forward with great anticipation to the first spin physics this year. l We look forward to mutually beneficial collaboration throughout the entire RHIC era.